Converting my LT15 from gas to Electric

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I've been reading in the knowledge base about the HP difference, but have to wonder about the RPMs.
My Kohler gas engine looks to run at 3500 rpms. I can pick up a 10 hp 3ph 1750 rpm with aluminum TEFC housing very cheap.
I have 600 amp 3 ph service at my shop, so having the power supply isn't an issue.

What I'm wondering is will that lower rpm be an issue, or does the drop in rpms while sawing with the gas engine get on down close to that, or do I need to plan on getting a 3500 electric to keep my blade speed up.

I can't go any larger with my motor drive pulley, due to the housing, and I don't know if they make another stepped pulley where the band is on a larger diameter, while the drive belt would be on a smaller diameter?

I can't seem to find the RPM'S for the electric motors on the Woodmizer site.
Are any of you running on electricity, and what RPM's does your motor run at?

Thanks Bob, My Kohler is 13 hp, with a 5" pulley.
I called Woodmizer this morning to ask what the rpms is on the 10 hp electric that they show on their site. And even though he was in parts department, it didn't show in his computer, so he couldn't tell me anything, even how much it weighed.

I did go ahead and picked up the motor this morning, with the understanding that I could return it if I can't make it work. Now that I have it to measure, I can see how it can be mounted closer toward the drive side, since it is narrower than the gas engine, which will allow me to use at least an 8" pulley on the motor, without making any modification to the housing.

And if I chose to cut the little housing cap part off above the drive belt, then fabricate a taller one, I could go on up to a 10" to get the same fpm to the blade.

I'd still like to hear from anyone using an electric motor what theirs is. Or even anyone running gas or diesel with a tachometer, what are your rpms when under load. I don't have a tac, but just go by ear to determine feed rate, striving to make a decent size chip, without overloading the motor, so I know my gas engine isn't running at full rpms, but I don't know how much lower.

I have some experience as maybe can help. In my log band saw the cutting speed is 28 meter per sec. It is a common speed for a lot of wood cotting tools. I have also used a log band saw with about the half speed, 16 m/sec. I think it works very good. You can expect a little slower feed but your blades will keep its sharpenes much longer.
The blade will cut a coarser saw dust and will stay fresh longer. I think you would try your electrical motor with a minimum of changes in your saw.
Good luck.

Thanks for the feedback P-O, I like the sound of that. I just took a closer look at it again, and I'm sure I can get an 8" motor pulley in there without changing the saw.
This would get me 2/3 of the desired or higher blade speed, while delivering more foot-pounds of power to the blade.

The new motor already has a 5" pulley on it, which is the same as the Koehler, so I can give it a try without even buying a new belt.

After you do this Keith, I hope you publish the results comparing the gas to the electric power wise. I have developed large single phase motors to replace gas engines. I would like to hear about real world experience. Bob

I want to add that I had a log band saw, years ago, with a two cyl Koeler, 19 Hp motor. The saw I have today has a 7,5 kW electric 3-phase motor. The saws are of the same size and the blade/cutting speed is nearly the same. I can say that the saw I have today, performs better. I have read that the manufactures of bigger log saws, reccomends to dubble the horse power, if you would go from electric to diesel motor. To change from a gasolin engine to an electric motor with 50% lower hp you would still have better performance.
In my oppinion the electic motor has a much better "answer" for load variations. Its torq character is better for log sawing.

Thank you PO for that information. 7.5 KW is about 10 HP. The advise I usually give is that if you are going from gas to electric is that you can reduce the size by about 50 percent. If anyone else wants to chime in,feel free to. Bob

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